Virtual reality systems provide users with the illusion that they are part of a “virtual” environment. A virtual reality system typically includes a computer processor, such as a personal computer or workstation, specialized virtual reality software, and virtual reality I/O devices such as head mounted displays, sensor gloves, three dimensional (“3D”) pointers, etc. These devices sense movement of a human body through a variety of sensors, and send signals to the computer processor to indicate the position and/or orientation of the human body in the virtual environment.
One common use for virtual reality systems is for training. In many fields, such as aviation, military and vehicle systems operation, virtual reality systems have been used successfully to allow a user to learn from and experience a realistic “virtual” environment. The appeal of using virtual reality systems for training relates, in part, to the ability of such systems to allow trainees the luxury of confidently operating in a highly realistic environment and making mistakes without “real world” consequences. Thus, for example, a trainee pilot or automobile driver can learn to operate a vehicle using a virtual reality simulator without concern for accidents that would cause injury, death and/or property damage in the real world. Similarly, operators of complex systems, e.g., nuclear power plants and weapons systems, can safely practice a wide variety of training scenarios that would risk life or property if performed in reality. In addition, virtual reality systems allow a user to handle and manipulate the controls of complicated and expensive vehicles and machinery. More specifically, a pilot or astronaut in training can operate a fighter aircraft or spacecraft by manipulating controls such as a control joystick and other buttons and view the results of controlling the aircraft on a virtual reality simulation of the aircraft in flight. In yet other applications, a user can manipulate objects and tools in the real world, such as a stylus, and view the results of the manipulation in a virtual reality world with a “virtual stylus” viewed on a screen, in 3-D goggles, etc.
For virtual reality systems to provide a realistic (and therefore effective) experience for the user, sensory feedback and manual interaction should be as natural as possible. As virtual reality systems become more powerful and as the number of potential applications increases, there is a growing need for an increased number of specific human/computer haptic interface devices or systems, which are specifically configured for a specific application (e.g. pilot, military or vehicle driving training). However, the availability of a number of specific human/computer haptic interface devices or systems is often inhibited by a number of technical and economic factors.